Recent surveys suggest that students have trouble applying mathematical and scientific procedures to practical problems. What appear to be lacking are a causal understanding of the underlying principles behind these procedures and linkages between abstract formulas and concrete everyday knowledge. This suggests that instructional techniques are needed that emphasize how knowledge is organized by students as well as what they know. It is argued that this requires new evaluation techniques that go beyond the traditional "percent correct" measures typically used in schools. It is proposed to adapt knowledge elicitation techniques that have been used to understand how experts solve practical problems to the classroom environment. It is hypothesized that an understanding of how experts solve practical problems can drive instructional methods to build better practical problem solving skills in students and that the knowledge elicitation tools used to evaluate expert knowledge can be used to evaluate the practical problem solving skills students are developing. In Phase I, both paper and pencil and a computerized proof of concept knowledge elicitation tools applicable to middle school mathematics students will be developed. These tools will be further developed and tested in Phase II.